Banca de QUALIFICAÇÃO: LEONARDO CARVALHO PALHANO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : LEONARDO CARVALHO PALHANO
DATE: 22/08/2024
TIME: 14:00
LOCAL: LabSis - UFRN
TITLE:

Extensional and compressional tectonic regimes affect the petrophysical properties of siliciclastic rocks of a damage zone in the Jatobá Basin, Brazil

KEY WORDS:

Ibimirim Fault, tectonic regimes, extensional and contractional deformation bands, petrophysical and structural characterization, damage zone, basin boundary fault

PAGES: 50
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUBÁREA: Geofísica
SPECIALTY: Geofísica Aplicada
SUMMARY:

It is known that damage zones that present cataclastic deformation bands (CDB) strongly affect fluid flow, storage capacity, and the effectiveness of the seal potential or of conduits. Damage zones and CDB could develop in the full range of tectonic regimes; the tectonic regime can dictate the type of CDB, related to kinematic spectrum between simple shear and pure compaction. However, the overlapping of extensional and contractional regime in the same basin, in the damage zone of the same fault, and in the same outcrop is still very poorly documented. This study was carried out on most suitable outcrop in the damage zone of the Ibimirim fault in the Jatobá basin, where the contractional regime are overlapping under the extensional regime. We integrated geological and structural mapping with petrographic, mineralogical, textural, microstructural, grain and pore data, as well 2D porosity and permeability. We identified three types of CDB, according to kinematics: (1) compaction shear bands in both regimes (CSB), (2) shear-enhanced deformation bands (SECB), and (3) pure compaction bands (PCB), both exclusive to the contractional regime. Thus, the CDB related to the extensional and contractional regimes, present significative differences in the ratios between shear and compaction and, consequently, in the amount of cataclastic matrix, which is reflected in the petrophysical properties. The CDB related to extensional regime, show porosity reductions from 1 to 2 orders of magnitude, while the contractional CDB bands reduces the interband space porosity by 1 order of magnitude, related to interband space and protolith. The extensional CDB reduces the interband space and protolith permeabilities by 4 and 5 orders of magnitude, while the contractional CDB decrease permeability from 1 to 2 orders of magnitude. In addition, contractional CDB are more porous than normal CDB by 1 order of magnitude, as well as contractional CDB are more permeable than extensional CDB by 3 orders of magnitude. Thus, the structural and petrophysical characterization of CDB developed in extensional and contractional regime plays a crucial role in the fluid flow and storage capacity in reservoirs that present more than one tectonic regime. 

COMMITTEE MEMBERS:
Presidente - 350640 - FRANCISCO HILARIO REGO BEZERRA
Externo à Instituição - DAVID LINO VASCONCELOS - UFCG
Externo à Instituição - FRANCISCO CEZAR COSTA NOGUEIRA - UFCG
Externo à Instituição - MATHEUS AMADOR NICCHIO - UFRJ